| picture frame vertebra | Radiographically diminished density of trabecular bone with relative preservation of the cortex, a sign of osteopenia. (05 Mar 2000) |
|---|---|
| pivot shift test | A manoeuvre to detect a deficiency of the anterior cruciate ligament of the knee; when the knee is extended, a sudden subluxation of the lateral tibial condyle upon the distal femur is positive. (05 Mar 2000) |
| Whitman's frame | A frame similar to the Bradford frame, but with curved sides. (05 Mar 2000) |
| Purkinje shift | <ophthalmology> In the light-adapted eye, the region of maximal brightness is in the yellow; in the dark-adapted eye, the region of maximal brightness is in the green. Synonym: Purkinje effect, Purkinje shift. (05 Mar 2000) |
| shift | 1. The act of shifting. Specifically: The act of putting one thing in the place of another, or of changing the place of a thing; change; substitution. "My going to Oxford was not merely for shift of air." (Sir H. Wotton) A turning from one thing to another; hence, an expedient tried in difficalty; often, an evasion; a trick; a fraud. "Reduced to pitiable shifts." "I 'll find a thousand shifts to get away." (Shak) "Little souls on little shifts rely." (Dryden) 2. Something frequently shifted; especially, a woman's under-garment; a chemise. 3. The change of one set of workmen for another; hence, a spell, or turn, of work; also, a set of workmen who work in turn with other sets; as, a night shift. 4. In building, the extent, or arrangement, of the overlapping of plank, brick, stones, etc, that are placed in courses so as to break joints. 5. <chemical> A breaking off and dislocation of a seam; a fault. 6. A change of the position of the hand on the finger board, in playing the violin. To make shift, to contrive or manage in an exigency. "I shall make shift to go without him." "[They] made a shift to keep their own in Ireland." (Milton) Origin: Cf. Icel skipti. See Shift. Source: Websters Dictionary (01 Mar 1998) |
| shift to the left | A marked increase in the percentage of immature cells in the circulating blood, based on the premise in haematology that the bone marrow with its immature myeloid cells is on the left, while the circulating blood with its mature neutrophils is on the right. Synonym: deviation to the left. See: maturation index. (05 Mar 2000) |
| shift to the right | In a differential count of white blood cells in the peripheral blood, the absence of young and immature forms. Synonym: deviation to the right. See: maturation index. (05 Mar 2000) |
| space frame | Three-dimensional optical bench that holds laser components stable from vibrational and thermal excursions. (09 Oct 1997) |
| Stryker frame | A frame that holds the patient and permits turning in various planes without individual motion of parts. (05 Mar 2000) |
| doppler shift | <radiobiology> The amount of change in the observed frequency of a wave due to the Doppler effect, sometimes called the Doppler frequency. (09 Oct 1997) |
| occluding frame | <dentistry> A special holder for models of your teeth. The articulator holds the models in the same alignment as your jaw so the orthodontist can look carefully at your bite. (08 Jan 1998) |
| open reading frame | <molecular biology> A reading frame in a sequence of nucleotides in DNA that contains no termination codons and so can potentially translate as a polypeptide chain. (18 Nov 1997) |
| overlapping reading frame | <molecular biology> Start codons in different reading frames which generate different polypeptides from the same DNA sequence. (09 Oct 1997) |
| threshold shift | Measurement of the degree of hearing loss or impairment in terms of a decibel shift from an individual's previous audiogram. (05 Mar 2000) |
| trial frame | A type of spectacle frame with variable adjustments, for holding trial lenses during refraction. (05 Mar 2000) |